How many times have they played in a dome since 2000? The schedulemakers are apparently in the Pats pocket as they keep making Indy play at Foxborough year after year, versus the other way around.
This is a myth that gets perpetuated because of playoff matchups, where the last two years they have taken place at New England. In fact, Indy has come to NE only this season and last season. In 2003 NE won @ Indianapolis. There's only a 3-year sampling. Either Indy would have had it or NE. Hardly a conspiracy theory of "year after year."
The reason they haven't played in many dome games is because they're not in the NFC. In the dome games they have played, they've won, including two Super Bowls. One of those being against the second-best scoring offense in NFL history. I think they hold their own.
As far as SD goes. Congratulations to them. Comparing how teams are Week 4 and how they are in January isn't that relevant, though. Especially with the injuries of then, and now.